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When doing G2 setup on mt 1031Q, looking into the lenses, on Red an Blue it's pitch black in there when G2 is turned down. But on my Green tube I can clearly see the tube face, even at the lowest setting. The raster DOES go out. Also I can see the previous menu screen from Avia for a short time. My RGB Gain controls are at their midpoints. Is this normal?


BTW: What setting should I have my contrast and brightness settings at when adjusting G2?


Jawhn
 

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Here are some recent comments from Ampro guru Walter Allen on "cold emission" (from Special Guest forum):


Regarding the inability to "cut off" the green tube, this is almost always due to a source of "cold emission", which is an always on, unwanted stream of electrons coming from some part of the electron gun. When present, this cold emission adds to the normal flow of electrons coming from the cathode, so even when the tube is truly cut off, you will seen a raster, although it will not be perfectly focused and there will be retrace lines since there it's always on. When you then turn up G2, you will see the normal raster appear in addition to the cold emission raster, but it will be focused and not exactly in the same place. You should use this focused raster to set the cutoff, while ignoring the cold emission. Note that even though the cold emission appears relatively bright while looking in through the lens, rarely is it bright enough to be seen on the screen, even with all colors cutoff.
 

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Also dont forget the green phosphor on some tubes will exhibit a long afterglow. So, if you turn G2 down all the way and the tube still glows try leaving it down a few minutes and see if it eventually goes away. You can also verify this by displaying a bright scene and then shutting the PJ down completely. You will probably see green continue to glow for a LONGGGGG time after the unit shuts off. In either case, this is normal...


--Kieth
 

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Personally I set my G2's to where the raster *Just* barely glows. And I mean you have to stare into the lens to see it. That way I don't worry that the green is different. At that point, it still is not enough to show anything on the screen.


Marc
 

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EXACTLY as marc states.


And you are seeing the green afterglow as to why you see the menue when the blue and red are black.


Just hold out a few minutes and the green will most likely be black too. If you notice when you kill the power at night, are you asking yoursef why the green tube is still on? It not its still glowing and if you look in the lense you will see the oulines of the last picture that was on the screen.


I remember my grandmother had an analog alarm clock that I used to play with when I was 6 years old. I would hold it up close to a bulb of a lamp to make it "charge up" then kill the lights so the numbers and dots on the face would illuminate really bright in the pitch black room.


After about a minute it would start to slowly fade away. This is actually the same thing in the green picture tube as the phosphers stop glowing after being excited by the electron beam!
 

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I think your Grandmas clock had Radioactive paint on the hands, people that worked in factory's that painted them used to lose their hands from cancer.
 

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I believe you're talking about "radium" that was used to make things glow WITHOUT having to expose it to a light first. A miner with a watch with radium painted hands could see the glowing during the entire shift. And yes, it killed many people who worked in the factory.
 

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I wear Tritium watches. I remember the old radium ones... lot's of casualties there.

Didn't a lot of those come from Russia back then before anyone knew how dangerous they were?


Marc
 
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